Drufo was an elderly squirrel who lived at Riftgard Fortress as a slave. He had a habit of repeating himself when he talked, and was close friends with Triss and her father Rocc Arrem. Before he was taken, he fought the Ratguards alongside Rocc in the mountains upriver. After the vermin killed Rocc with arrows, Drufo and a very young Triss were captured by the slavers.
Many seasons later, Drufo was one of the forced assistants for Princess Kurda's sword exercises, throwing vegetables for the ferret to slice, and secretly cleaning up the mess afterwards to feed to the other slaves. After Triss, Shogg, and Welfo were placed into one of the punishment cages for execution, he gave them a file to cut through the iron bars.
When the trio broke out of the cage, Drufo led a small slave rebellion to cause a distraction. In the melee, he stole Ratguard lieutenant Flith's spear, and guarded the jetty from the oncoming vermin. Triss tried to motivate him to swim out to the ship and leave with the escapees, but he refused, telling her that he planned on making a stand and dying in battle in order to buy the runaways enough time to sail safely away.
Drufo was killed by Princess Kurda, who ran him through with her sabre.